Experimental study on the improving the efficiency of oil displacement by co-using of the steam-solvent catalyst

This work presents the results of physical modeling of the process of steam stimulation together with solvent and catalyst injection on a bulk core model to increase the recovery factor (RF) of high-viscosity oil from the May-orovskoye heavy oil field. A series of filtration experiments was carried out to select the optimal injection modes and conditions. The process of steam stimulation treatment of Mayorovskoye high-viscosity oil, were carried out in an autoclave reactor at a temperature of 300°C for 24 h in a nitrogen atmos-phere with adding a catalyst precursor based on transition metals iron and nickel in a ratio of 85:15 was selected. The dosage in terms of catalytically active metals is selected in the amount of 0.2 wt.% (oil-soluble catalyst precur-sor) into a preheated model, which simulates catalyst injection between the cycles of the process of cyclic steam stimulation, the active form of the catalyst is formed. The catalyst precursor is transformed into ultrafine particles containing transition metal oxides and sulfides. According to SEM data, the particle diameter of the active form of the catalyst is less than 80 nm. Com-bined injection of a solvent with steam and a mixture of solvent and catalyst with steam leads to an increase in displacement efficiency compared to the standard method of steam injection. With additional exposure of the solvent and catalyst solution in the heated reservoir model, the displacement efficiency largely increases. This is associated with an increase in the potential upgrading degree of oil from the Mayorovskoye field. It has been found that catalyst injection is most effective if the formation is preheated and held be-fore steam treatment